MBS Protocol
PLX30 Series
User Manual
Ethernet and Serial Gateways
Page 124 of 200
ProSoft Technology, Inc.
September 19, 2012
7.1
MBS Functional Overview
The Modbus Serial protocol supports both Master and slave implementations of
the protocol. Each of the gateway serial ports is individually configurable to
communicate to separate networks.
7.1.1 Modbus Serial Specifications
Command List
Up to 100 commands per Master port, each fully
configurable for Function Code, slave address, register
to/from addressing and word/bit count.
Supported Modbus
Function Codes
1: Read Coil Status
2: Read Input Status
3: Read Holding Registers
4: Read Input Registers
5: Force (Write) Single Coil
6: Preset (Write) Single Holding Register
15: Force (Write) Multiple Coils
16: Preset (Write) Multiple Holding Registers
Polling of Command
List
Configurable polling of command list, including continuous
and on change of data, and dynamically user or automatic
enabled.
Status Data
Error codes available on an individual command basis. In
addition, a slave status list is maintained per active Modbus
Master port.
Node Address
1 to 247 (software selectable)
RS Interface
RS232, RS422, and RS485
